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271.
For 19 mating-relevant traits, single males (N= 53) and single females (N= 86) rated (a) themselves relative to their same-sex peers, (b) their perceptions of the qualities desired by members of the opposite sex in an ideal partner, and (c) the qualities desired in their own ideal romantic partner. Several themes emerged from the data. First, males’ and females’ judgments of what members of the opposite-sex seek were generally accurate. Second, males and females both feel that they fall short of perceived opposite-sex expectations in a few areas. Third, both males and females desire an ideal partner better than themselves, but this is especially true for females. These findings are discussed in terms of evolutionary social psychological principles.  相似文献   
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Studies of appetite in mammals emphasize that meal size is learned, but lactation and parental care constrain testing of naive individuals. Neonatal reptiles, in contrast, are self-sufficient foragers. The authors examined the effect of prey size on meal size in primivorous (at first feeding) northern watersnakes (Nerodia sipedon). When offered an excess of small prey (2%-20% of snake mass), neonates ate significantly smaller meals (M = 23.5% of snake mass) than when offered a single huge item (range = 32%-55%). The authors conclude that (a) the taking of smaller meals is not a learned effect, (b) there may be a satiety threshold for meal size rather than a target, (c) oropharyngeal stimuli may provide satiety cues, and (d) huge meals may have fitness costs.  相似文献   
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Based on computational models of the hippocampus, it has been suggested that a possible mechanism for memory retrieval is pattern completion, wherein an autoassociative network recalls previous patterns of activity given noisy or degraded cues. However, there are few behavioral data examining pattern completion per se in the hippocampus. Here, we present a study in which rats were tested on a spatial location retrieval paradigm, each trial of which consisted of a sample and choice phase. During the sample phase, rats were trained to displace an object in one of 15 possible locations to retrieve a food reward and return to the start-box on a cheeseboard maze. The object was then removed and the same location was re-baited for the choice phase. The rats' accuracy in returning to the correct location was recorded. On test trials, visual extramaze cues, vestibular cues, or both were manipulated to assess pattern completion in normal rats. Subjects were then randomly assigned to receive a cortical control, a sham, or a dorsal and ventral hippocampal lesion and were retested on the task. Control and unoperated rats were able to perform the task when visual extramaze or vestibular cues were reliable, but not when they were manipulated. Rats with hippocampal lesions were impaired in the baseline condition, as well as during all manipulations. These results support the hypothesis that the hippocampus supports the retrieval of a spatial location, possibly through a process of pattern completion.  相似文献   
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The relative effectiveness of explicit instruction, guided discovery, and discovery learning techniques in enhancing anticipation skill in young, intermediate-level tennis players was examined. Performance was assessed pre- and postintervention, during acquisition, and under transfer conditions designed to elicit anxiety through the use of laboratory and on-court measures. The 3 intervention groups improved from pre- to posttest compared with a control group (n = 8), highlighting the benefits of perceptual-cognitive training. Participants in the explicit (n = 8) and guided discovery (n = 10) groups improved their performance during acquisition at a faster rate than did the discovery learning (n = 7) group. However, the explicit group showed a significant decrement in performance when tested under anxiety provoking conditions compared with the guided discovery and discovery learning groups. Although training facilitated anticipation skill, irrespective of the type of instruction used in this experiment, guided discovery methods are recommended for expediency in learning and resilience under pressure.  相似文献   
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Cruelty to animals may be a particularly pernicious aspect of problematic child development. Progress in understanding the development of the problem is limited due to the complex nature of cruelty as a construct, and limitations with current assessment measures. The Children and Animals Inventory (CAI) was developed as a brief self- and parent-report measure of F. R. Ascione's (1993) 9 parameters of cruelty. The CAI emerged as a reliable, stable, and readily utilized measure of cruelty using parent and child reports. Children (especially the older children) reported higher rates of cruelty than their parents and boys reported more cruelty than girls. Self- and parent-reports showed good convergence with independent observations of cruelty versus nurturance during free interactions with domestic animals. The results indicate that cruelty to animals can be reliably measured using brief child and parent report measures.  相似文献   
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